The present invention generally relates to hybrid electric and bleed architectures for aircraft and more specifically, to systems and methods for finding the right balance between electric power and bleed power in order to match or improve current more electric architecture (MEA) performance while simplifying power extraction from the engines as well as simplifying the electrical system.
Many of today's aircraft use the extraction of thrust engine compressor bleed air to power the aircraft cabin and cargo ventilation system, the environmental control system (ECS), the wing and cowl anti-ice system (WAI) and the engine start system. The extraction of engine cycle compressor core bleed air places a significant penalty on the engine cycle, reducing engine efficiency. Much of the power inherent in the extracted bleed air, before the power is delivered to and used by the aircraft systems, is purposely wasted by pressure and temperature reduction in the bleed air control and distribution system to ensure that the hot bleed air conforms to aircraft material limits and is suitable for use by the aircraft systems. The bleed air extraction and distribution equipment required to use engine bleed air is expensive to purchase and install, heavy, and relatively unreliable.
Because of the above issues, the aircraft industry is moving toward more electric architectures. Even if, in most cases, electrifying aircraft systems can generate value, it is not always true and creates additional complexity on the electrical systems that can be difficult to justify.
U.S. Pat. No. 6,704,635 describes an electric based environmental control system (ECS) and cabin pressurization system. The only use of engine bleed air is for engine cowl anti-ice via a single bleed port. There is no teaching of optimizing the engine bleed air for ECS or cabin pressurization.
As can be seen, there is a need for an improved hybrid electric and engine bleed architecture in an aircraft that may provide for optimal use of bleed air for ECS and/or cabin pressurization.